How to install Scala on Debian/Ubuntu (Scala 2.9.0.1, 2.8.1)

Update: Scala 2.9.0.1 (hotfixes to 2.9.0, released on May 12) was released on May 25, 2011. In this tip you can find a way how to install it (and older version - 2.8.1) onto yours Ubuntu/Debian box.

Ubuntu default apt repository gives us option to install only scala-2.7.7, but if you want to use latest version of scala (2.9.0.1 2.8.1 to date when this tip was written), so all what we need to do is this actions: